plague-client - Server returned an error: insufficient privileges

Hi. I have been following the wiki pages for creating an EPEL package
from a Fedora package. I got an EL-5 branch in the package CVS module.
However when I do "make build" in that branch I get the error on the
subject line. I can't find any reference in documentation regarding
this. All the "make build" does is the following:
/usr/bin/plague-client build prover9 prover9-200805a-4_el5 el5
which seems correct and the wiki docs imply this should just work.
Does anyone know what might be causing this error or is there a
missing step somewhere that is needed to submit an EPEL package?
Did find one reference to the ~/.plague-client.cfg file which
suggested the config on the wiki may be out of date so I include
mine below in case that sheds any light on the issue:
[Certs]
user-ca-cert = ~/.fedora-upload-ca.cert
server-ca-cert = ~/.fedora-server-ca.cert
user-cert = ~/.fedora.cert
[User]
email = timc inf ed ac uk
[Server]
use_ssl = True
allow_uploads = False
address = https://buildsys.fedoraproject.org:8887
The certificates work fine for other Fedora operations and doing builds
with Koji etc. so I don't think the problem lies with them.
After looking at the source I also tried some values for "upload_user"
in the config file since the local account is under a different uid
from the FAS account but that didn't seem to help.
There was also a suggestion there may be a firewall issue?
Cheers,
Tim.
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